Fix an unhandled exception when sort_strict=true but sort_by is unspe… #259

	# This is a basic workflow to help you get started with Actions

	name: CI

	# Controls when the action will run. Triggers the workflow on push or pull request
	# events but only for the master branch
	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	# This workflow contains a single job called "build"
	build:
	# The type of runner that the job will run on
	runs-on: macos-12

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- uses: actions/checkout@v2

	- name: Install build dependencies via homebrew
	run: \|
	echo Installing the OCaml toolchain
	brew install gpatch
	brew install ocaml opam
	opam init -y

	- name: Install OCaml dependencies from opam
	run: \|
	echo Installing OCaml dependencies
	opam install -y --deps-only .

	- name: Build soupault
	run: \|
	eval $(opam env)
	dune build

	- uses: actions/upload-artifact@v2
	with:
	name: soupault
	path: _build/default/src/soupault.exe
	if-no-files-found: error

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